63_Notches in rear main bearing

[Steve D.]

When I pulled the rear main bearing cap to replace the seal (chasing a leak) I noticed that there were notches positioned at 5 and 7 o'clock on both the front and back of the bearing skirt (see photos). What would cause this?

Steve

[Joe L.]

Re: 63_Notches in rear main bearing

When I pulled the rear main bearing cap to replace the seal (chasing a leak) I noticed that there were notches positioned at 5 and 7 o'clock on both the front and back of the bearing skirt (see photos). What would cause this?

Steve

Steve-----


My vague recollection is that the thrust surface of the rear main bearing is manufactured this way. I expect it's to improve lubrication of the thrust surface.

[Stuart F.]

Re: 63_Notches in rear main bearing

Although the pictures aren't perfectly clear, if this is the thrust surface then, yes as Joe said. Most thrust bearings/washers will have some sort of notches, grooves or reliefs which are needed to hold oil as the clearance will normally vary slightly while in use, i.e. as they are not designed (or expected) to hold a film of oil under pressure like the journals.

Does that sound about right?

Stu Fox

[Steve D.]

Re: 63_Notches in rear main bearing

Joe / Stu

Thanks. I was hoping that was the case.

Steve

[Clem Z.]

Re: 63_Notches in rear main bearing

Although the pictures aren't perfectly clear, if this is the thrust surface then, yes as Joe said. Most thrust bearings/washers will have some sort of notches, grooves or reliefs which are needed to hold oil as the clearance will normally vary slightly while in use, i.e. as they are not designed (or expected) to hold a film of oil under pressure like the journals.

Does that sound about right?

Stu Fox

correct as pushing in the clutch put extra pressure on the rear main thrust surface so you need a place for the oil to be able to flow freely